The MAR-Vema Fracture Zone intersection surveyed by deep submersible Nautile     

Jean-Marie Auzende  Daniel Bideau  Enrico Bonatti  Mathilde Cannat  José Honnorez  Yves Lagabrielle  Jacques Malavieille  Vassilios Mamaloukas-Frangoulis  Catherine Mével 《地学学报》1990,2(1):68-73

One of the two objectives of the Vemanaute cruise of the French deep submersible Nautile, was the geological study of the eastern intersection area between the Mid-Atlantic Ridge (MAR) and the Vema Fracture Zone in the equatorial Atlantic. Fourteen dives were conducted that allowed detailed geological survey and sampling of the main morphostructural units of this area: the northern and southern walls of the fracture zone, the median ridge, the northern and southern troughs and the nodal basin. In situ observations of recent tectonic features such as furrows, ridges and circular depressions, concentrated within the southern trough, allowed us to establish the location and the size of the present-day displacement zone. Geological investigations have shown that the nodal basin is entirely floored by basalts thus contrasting with other equivalent areas such as the Kane and Oceanographer fracture zone-MAR eastern intersections. Finally, this study stresses the great opposition between the relatively old and tectonically inactive northern part of the fracture, and the southern part which shows active tectonics and recent volcanic activity.  相似文献   

The Spectrum-UV Mission: an International Ultraviolet Observatory     

Enrico G. Tanzi  Alexander A. Boyarchuk  Michael Grewing  Nikolaj V. Steshenko 《Experimental Astronomy》1997,7(4):345-359

The Spectrum-UV Mission is an ultraviolet space observatory, scheduled to be launched at the break of the century into a 7-day, highly excentric orbit aboard a Spectrum Series platform. The Observatory is endowed with a 170-cm aperture telescope and a focal plane instrument complement for spectroscopy and imaging in the 912 to 3600 range. The results of an advanced feasibility study, being carried out in the four partecipating Countries (Germany, Italy, Russia and Ukraine) are presented.  相似文献   

Investigating fossil hydrothermal systems by means of fluid inclusions and stable isotopes in banded travertine: an example from Castelnuovo dell’Abate (southern Tuscany,Italy)     

Valentina Rimondi  Pilario Costagliola  Giovanni Ruggieri  Marco Benvenuti  Chiara Boschi  Andrea Brogi  Enrico Capezzuoli  Guia Morelli  Massimo Gasparon  Domenico Liotta 《International Journal of Earth Sciences》2016,105(2):659-679

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Analysis of spatial and temporal rainfall trends in Sicily during the 1921–2012 period     

Lorena Liuzzo  Enrico Bono  Vincenzo Sammartano  Gabriele Freni 《Theoretical and Applied Climatology》2016,125(1-2):113-130

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Exploration of spatiotemporal and semantic clusters of Twitter data using unsupervised neural networks     

Enrico Steiger  Bernd Resch  Alexander Zipf 《International journal of geographical information science》2016,30(9):1694-1716

ABSTRACT

The investigation of human activity patterns from location-based social networks like Twitter is an established approach of how to infer relationships and latent information that characterize urban structures. Researchers from various disciplines have performed geospatial analysis on social media data despite the data’s high dimensionality, complexity and heterogeneity. However, user-generated datasets are of multi-scale nature, which results in limited applicability of commonly known geospatial analysis methods. Therefore in this paper, we propose a geographic, hierarchical self-organizing map (Geo-H-SOM) to analyze geospatial, temporal and semantic characteristics of georeferenced tweets. The results of our method, which we validate in a case study, demonstrate the ability to explore, abstract and cluster high-dimensional geospatial and semantic information from crowdsourced data.  相似文献   

An approximate analytical representation of the atmospheric gamma-ray flux at balloon altitudes     

Enrico Costa  Enrico Massaro  Marco Salvati  Antonio Appolloni 《Astrophysics and Space Science》1984,100(1-2):165-174

The general behaviour of the atmospheric -ray flux as a function of the residual atmosphere, zenith angle, and photon energy is approximated with simple analytical expressions. The free parameters are determined by comparison with the most recent models and the existing experimental measurements. The resulting formulae have an accuracy comparable to the mutual consistency of the available pieces of information, and at the same time are very convenient to use in numerical simulations.  相似文献   

Hubble Space Telescope survey of the Perseus Cluster – I. The structure and dark matter content of cluster dwarf spheroidals     

Samantha J. Penny  Christopher J. Conselice  Sven De Rijcke  Enrico V. Held 《Monthly notices of the Royal Astronomical Society》2009,393(3):1054-1062

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旋转扰动流体中壁面湍流不稳定及其拟序结构研究Ⅰ:实验     

Enrico Ferrero  张瑛  全利红  Luca Mortarini  Renato Forza 《气象与减灾研究》2009,32(3)

重点介绍和讨论了中性条件下旋转扰动流体中边界层强迫不稳定及其相关的一些问题,阐述了旋转体系中切变驱动边界层不稳定的动力学特征.这些不稳定状态的研究在大气物理学、流体动力学、海洋学等多个领域中引起科学家极大的兴趣,近年来在实验和理论研究中都得到了不断的发展.意大利都灵大学基础物理系地球科学实验组通过水槽旋转实验方法,不断改变水槽启动或结束时的旋转运动速度,以及底部壁面粗糙度等要素,所得到的实验结果与SDBL理论非常一致.  相似文献   

Issues associated with the distinction between climatic and tectonic controls on Permian alluvial fan deposits from the Kotzen and Barnim Basins (North German Basin)     

Enrico Kallmeier  Christoph Breitkreuz  Hubert Kiersnowski  Marion Geißler 《Sedimentary Geology》2010,223(1-2):15-34

Facies analysis focussing on coarse-grained sediments has been carried out on more than 2500 m of drill cores from seven wells from southern margins of the North German Basin (NGB). The NGB forms a central element of the Southern Permian Basin (SPB). The wells exposed conglomerates and sandstones of the Rotliegend Grüneberg and Parchim Formations deposited in the Kotzen Basin and the Barnim Basin.17 lithofacies types have been grouped into six lithofacies associations. The studied successions are dominated by fluid gravity flow deposits (hyperconcentrated flows and stream flows) of alluvial fan and alluvial plain systems. Maximum particle size/bed thickness plots (MPS/BTh) support the interpretation as fluid gravity flow deposits. The MPS and BTh data have also been used to differentiate coarsening–thickening and fining–thinning trends of the fan systems.The dominance of water-rich mass flow processes together with sedimentary structures such as dewatering structures and outwashed tops suggests the presence of wet-type fans and plains under semi-humid to semi-arid seasonal climates in the central SPB. The investigated sediments show variation in clast composition subsequent to deep erosion processes on basin margins and changes of source areas. Synsedimentary normal faults and clastic dykes have been interpreted as indicators of tectonic activity of grabens itself and its frames. On a larger scale, then evolution from a half-graben to a graben is apparent for the Tuchen Sub-basin at least. The progradational/retrogradational cycles of the studied alluvial fan systems document combined local tectonic movements and influences of climatic changes. However, our data did not allow for a clear distinction between climatic and tectonic signals. Furthermore, a one-to-one correlation of fan cycles with depositional trends in the NGB basin centre would appear to be oversimplistic.  相似文献   

Studying travertines for neotectonics investigations: Middle–Late Pleistocene syn-tectonic travertine deposition at Serre di Rapolano (Northern Apennines, Italy)     

Andrea Brogi  Enrico Capezzuoli  Riccardo Aqué  Marilì Branca  Mario Voltaggio 《International Journal of Earth Sciences》2010,99(6):1383-1398

Middle–Late Pleistocene tectonic activity has been inferred through studies on travertine deposits exposed in a tract of the hinterland Northern Apennines. A detailed study on the relationships between tectonics and travertine deposition coupled with ²³⁰Th/²³⁴U age determination of travertines at Cava Oliviera quarry, located close to Serre di Rapolano village (southern Tuscany, Northern Apennines), allowed us to recognise Pleistocene faults, whose activity has been referred to 157–24 ka, at least. Travertine deposition was tectonically controlled by WSW-ENE striking, oblique and normal faults, associated to a main fault (named as the Violante Fault). This structure dissected a regional normal fault (known as the Rapolano Fault) Early–Middle Pliocene in age, which bounded the eastern side of the Pliocene Siena Basin, and gave rise to space accommodation for clayey and sandy marine sediments. Hydrothermal circulation (and related travertine deposition) was favoured by the damaging enhancement due to the fault–fault intersection. Tectonic activity has been also documented by deformation recorded by travertines, which suggest a main tectonic event between 64 ± 5 and 40 ± 5 ka. The tectonic activity described for the study area agrees with the Quaternary tectonic evolution documented in the surrounding areas (e.g. Mt. Amiata and Mt. Vulsini), as well as the Tyrrhenian margin of the Central Apennines, indicating that a widespread tectonic activity affected the inner part of the Apennines until the latest Quaternary.  相似文献